AVS 51st International Symposium
    Vacuum Technology Tuesday Sessions
       Session VT-TuP

Paper VT-TuP15
Vacuum Conditions in the Vicinity of a Field Emitter

Tuesday, November 16, 2004, 4:00 pm, Room Exhibit Hall B

Session: Poster Session
Presenter: M. Zumer, Jozef Stefan Institute, Slovenia
Authors: M. Zumer, Jozef Stefan Institute, Slovenia
B. Zajec, Jozef Stefan Institute, Slovenia
V. Nemanic, Jozef Stefan Institute, Slovenia
Correspondent: Click to Email
A basic characterization of novel field emitters is usually realized in a standard UHV chamber equipped with appropriate pumps. Their high pumping speed and the remote location of the vacuum gauge prevents to monitor the pressure changes during operation of the field emitter (FE). In most of the potential applications the FE runs in a small sealed device where the local pressure is frequently unknown and its influence on the device lifetime is often underestimated. A small glass envelope equipped with a miniature ion getter pump (IG), spinning rotor gauge (SRG) and a cathodoluminescent screen, was prepared to monitor properly these phenomena. The IG discharge current was calibrated versus pressure by the means of the SRG. Single-crystalline nanoparticles deposited onto molybdenum needles were used as field emitters. The initial pressure in a well outgassed envelope was in the UHV range, but its increase for three orders of magnitude was detected when the field emission current reached one microampere range at 1kV. A good correlation between the FE current and electron stimulated desorbed gases was found.